Finding the Fourth Proportional to 1,434.85, 1,980.05 and 845.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,434.85 : 1,980.05 = 845.78 : x
2. Step 2: Convert to fraction form
   1,434.85/1,980.05 = 845.78/x
3. Step 3: Cross multiply
   1,434.85x = 1,980.05 × 845.78
4. Step 4: Simplify right side
   1,434.85x = 1,674,672.56
5. Step 5: Solve for x
   x = 1,674,672.56/1,434.85
6. Step 6: Final answer
   x = 1,167.14